lix/src/libstore/local-store.hh
Eelco Dolstra a737f51fd9 Retry all SQLite operations
To deal with SQLITE_PROTOCOL, we also need to retry read-only
operations.
2013-10-16 15:58:20 +02:00

346 lines
9.6 KiB
C++

#pragma once
#include <string>
#include "store-api.hh"
#include "util.hh"
#include "pathlocks.hh"
class sqlite3;
class sqlite3_stmt;
namespace nix {
/* Nix store and database schema version. Version 1 (or 0) was Nix <=
0.7. Version 2 was Nix 0.8 and 0.9. Version 3 is Nix 0.10.
Version 4 is Nix 0.11. Version 5 is Nix 0.12-0.16. Version 6 is
Nix 1.0. Version 7 is Nix 1.3. */
const int nixSchemaVersion = 7;
extern string drvsLogDir;
struct Derivation;
struct OptimiseStats
{
unsigned long totalFiles;
unsigned long sameContents;
unsigned long filesLinked;
unsigned long long bytesFreed;
unsigned long long blocksFreed;
OptimiseStats()
{
totalFiles = sameContents = filesLinked = 0;
bytesFreed = blocksFreed = 0;
}
};
struct RunningSubstituter
{
Path program;
Pid pid;
AutoCloseFD to, from, error;
FdSource fromBuf;
bool disabled;
RunningSubstituter() : disabled(false) { };
};
/* Wrapper object to close the SQLite database automatically. */
struct SQLite
{
sqlite3 * db;
SQLite() { db = 0; }
~SQLite();
operator sqlite3 * () { return db; }
};
/* Wrapper object to create and destroy SQLite prepared statements. */
struct SQLiteStmt
{
sqlite3 * db;
sqlite3_stmt * stmt;
unsigned int curArg;
SQLiteStmt() { stmt = 0; }
void create(sqlite3 * db, const string & s);
void reset();
~SQLiteStmt();
operator sqlite3_stmt * () { return stmt; }
void bind(const string & value);
void bind(int value);
void bind64(long long value);
void bind();
};
class LocalStore : public StoreAPI
{
private:
typedef std::map<Path, RunningSubstituter> RunningSubstituters;
RunningSubstituters runningSubstituters;
Path linksDir;
public:
/* Initialise the local store, upgrading the schema if
necessary. */
LocalStore(bool reserveSpace = true);
~LocalStore();
/* Implementations of abstract store API methods. */
bool isValidPath(const Path & path);
PathSet queryValidPaths(const PathSet & paths);
PathSet queryAllValidPaths();
ValidPathInfo queryPathInfo(const Path & path);
Hash queryPathHash(const Path & path);
void queryReferences(const Path & path, PathSet & references);
void queryReferrers(const Path & path, PathSet & referrers);
Path queryDeriver(const Path & path);
PathSet queryValidDerivers(const Path & path);
PathSet queryDerivationOutputs(const Path & path);
StringSet queryDerivationOutputNames(const Path & path);
Path queryPathFromHashPart(const string & hashPart);
PathSet querySubstitutablePaths(const PathSet & paths);
void querySubstitutablePathInfos(const Path & substituter,
PathSet & paths, SubstitutablePathInfos & infos);
void querySubstitutablePathInfos(const PathSet & paths,
SubstitutablePathInfos & infos);
Path addToStore(const Path & srcPath,
bool recursive = true, HashType hashAlgo = htSHA256,
PathFilter & filter = defaultPathFilter, bool repair = false);
/* Like addToStore(), but the contents of the path are contained
in `dump', which is either a NAR serialisation (if recursive ==
true) or simply the contents of a regular file (if recursive ==
false). */
Path addToStoreFromDump(const string & dump, const string & name,
bool recursive = true, HashType hashAlgo = htSHA256, bool repair = false);
Path addTextToStore(const string & name, const string & s,
const PathSet & references, bool repair = false);
void exportPath(const Path & path, bool sign,
Sink & sink);
Paths importPaths(bool requireSignature, Source & source);
void buildPaths(const PathSet & paths, bool repair = false);
void ensurePath(const Path & path);
void addTempRoot(const Path & path);
void addIndirectRoot(const Path & path);
void syncWithGC();
Roots findRoots();
void collectGarbage(const GCOptions & options, GCResults & results);
/* Optimise the disk space usage of the Nix store by hard-linking
files with the same contents. */
void optimiseStore(OptimiseStats & stats);
/* Optimise a single store path. */
void optimisePath(const Path & path);
/* Check the integrity of the Nix store. Returns true if errors
remain. */
bool verifyStore(bool checkContents, bool repair);
/* Register the validity of a path, i.e., that `path' exists, that
the paths referenced by it exists, and in the case of an output
path of a derivation, that it has been produced by a successful
execution of the derivation (or something equivalent). Also
register the hash of the file system contents of the path. The
hash must be a SHA-256 hash. */
void registerValidPath(const ValidPathInfo & info);
void registerValidPaths(const ValidPathInfos & infos);
/* Register that the build of a derivation with output `path' has
failed. */
void registerFailedPath(const Path & path);
/* Query whether `path' previously failed to build. */
bool hasPathFailed(const Path & path);
PathSet queryFailedPaths();
void clearFailedPaths(const PathSet & paths);
void vacuumDB();
/* Repair the contents of the given path by redownloading it using
a substituter (if available). */
void repairPath(const Path & path);
/* Check whether the given valid path exists and has the right
contents. */
bool pathContentsGood(const Path & path);
void markContentsGood(const Path & path);
void setSubstituterEnv();
private:
Path schemaPath;
/* Lock file used for upgrading. */
AutoCloseFD globalLock;
/* The SQLite database object. */
SQLite db;
/* Some precompiled SQLite statements. */
SQLiteStmt stmtRegisterValidPath;
SQLiteStmt stmtUpdatePathInfo;
SQLiteStmt stmtAddReference;
SQLiteStmt stmtQueryPathInfo;
SQLiteStmt stmtQueryReferences;
SQLiteStmt stmtQueryReferrers;
SQLiteStmt stmtInvalidatePath;
SQLiteStmt stmtRegisterFailedPath;
SQLiteStmt stmtHasPathFailed;
SQLiteStmt stmtQueryFailedPaths;
SQLiteStmt stmtClearFailedPath;
SQLiteStmt stmtAddDerivationOutput;
SQLiteStmt stmtQueryValidDerivers;
SQLiteStmt stmtQueryDerivationOutputs;
SQLiteStmt stmtQueryPathFromHashPart;
/* Cache for pathContentsGood(). */
std::map<Path, bool> pathContentsGoodCache;
bool didSetSubstituterEnv;
int getSchema();
void openDB(bool create);
void makeStoreWritable();
unsigned long long queryValidPathId(const Path & path);
unsigned long long addValidPath(const ValidPathInfo & info, bool checkOutputs = true);
void addReference(unsigned long long referrer, unsigned long long reference);
void appendReferrer(const Path & from, const Path & to, bool lock);
void rewriteReferrers(const Path & path, bool purge, PathSet referrers);
void invalidatePath(const Path & path);
/* Delete a path from the Nix store. */
void invalidatePathChecked(const Path & path);
void verifyPath(const Path & path, const PathSet & store,
PathSet & done, PathSet & validPaths, bool repair, bool & errors);
void updatePathInfo(const ValidPathInfo & info);
void upgradeStore6();
void upgradeStore7();
PathSet queryValidPathsOld();
ValidPathInfo queryPathInfoOld(const Path & path);
struct GCState;
void deleteGarbage(GCState & state, const Path & path);
void tryToDelete(GCState & state, const Path & path);
bool canReachRoot(GCState & state, PathSet & visited, const Path & path);
void deletePathRecursive(GCState & state, const Path & path);
bool isActiveTempFile(const GCState & state,
const Path & path, const string & suffix);
int openGCLock(LockType lockType);
void removeUnusedLinks(const GCState & state);
void startSubstituter(const Path & substituter,
RunningSubstituter & runningSubstituter);
string getLineFromSubstituter(RunningSubstituter & run);
template<class T> T getIntLineFromSubstituter(RunningSubstituter & run);
Path createTempDirInStore();
Path importPath(bool requireSignature, Source & source);
void checkDerivationOutputs(const Path & drvPath, const Derivation & drv);
void optimisePath_(OptimiseStats & stats, const Path & path);
// Internal versions that are not wrapped in retry_sqlite.
bool isValidPath_(const Path & path);
void queryReferrers_(const Path & path, PathSet & referrers);
};
typedef std::pair<dev_t, ino_t> Inode;
typedef set<Inode> InodesSeen;
/* "Fix", or canonicalise, the meta-data of the files in a store path
after it has been built. In particular:
- the last modification date on each file is set to 1 (i.e.,
00:00:01 1/1/1970 UTC)
- the permissions are set of 444 or 555 (i.e., read-only with or
without execute permission; setuid bits etc. are cleared)
- the owner and group are set to the Nix user and group, if we're
in a setuid Nix installation. */
void canonicalisePathMetaData(const Path & path, uid_t fromUid, InodesSeen & inodesSeen);
void canonicalisePathMetaData(const Path & path, uid_t fromUid);
void canonicaliseTimestampAndPermissions(const Path & path);
MakeError(PathInUse, Error);
/* Whether we are root. */
bool amPrivileged();
/* Recursively change the ownership of `path' to the current uid. */
void getOwnership(const Path & path);
/* Like deletePath(), but changes the ownership of `path' using the
setuid wrapper if necessary (and possible). */
void deletePathWrapped(const Path & path, unsigned long long & bytesFreed);
void deletePathWrapped(const Path & path);
}